Calorie Calculator

How many calories should you eat?

This calculator builds directly on your TDEE (Total Daily Energy Expenditure) and doesn't use a new formula of its own. It runs the same Mifflin-St Jeor-based calculation, adjusts it for your activity level, then adds or subtracts calories based on the goal you pick below: losing weight, gaining weight, or staying the same.

The 7,700 kcal rule of thumb

A commonly cited rule of thumb treats roughly 7,700 kcal as equal to about 1 kg of body fat, so a daily deficit of 500 kcal works out to roughly 0.5 kg of weight loss a week. It's a useful planning number, not a precise law: real weight change isn't perfectly linear, day-to-day shifts are often water weight rather than fat, and metabolism tends to adapt somewhat as weight changes, so results usually slow down over time even at a steady deficit.

Deficit and surplus ranges

The calculator above uses fixed adjustments, but a realistic range looks like this:

Aggressive deficits lose weight faster on paper, but they're harder to sustain and more likely to cost muscle along with fat. A mild deficit is usually the more durable choice.

When to be careful

Very low intakes aren't something to reach for without guidance. As a general rule, going below roughly 1,200 kcal a day for women or 1,500 kcal a day for men isn't recommended without medical supervision. This isn't medical advice, just a widely cited floor worth knowing before cutting calories aggressively.

Limitations

This number is only as accurate as the TDEE it's built on, and TDEE itself is an estimate with a real-world margin of error. It also doesn't account for individual differences in how bodies respond to a deficit or surplus, water retention, or changes in activity level over time. Treat it as a starting point and adjust based on how your weight actually trends over a few weeks.